Dental articulator.



A. GYSL DENTAL ARTICULATOR.

APPLIQATION FILED MAY 10. 1916.

Patented June 5, 1917.

3 SHEETS-SHEET 1.

A. GYSI.

DENTAL ARTICULATOR.

APPLICATION FILED MAY 10. 1916.

Patented June 5,1917.

3 SHEETS-SHEET 2.

A. GYS'I.

DENTAL ARTICULATOR.

APPLICATION FILED MAY l0. I915.

L%%&fifi?y V PatentedJune 5,1917.

3 SHEETS-SHEET 3- W W W ALFRED GYSI, 0F ZURICH, SWITZERLAND.

DENTAL ARTICULATOR.

mas er.

Specification of Letters Patent.

Patented June 5, 191?.

Application filed May 10, 1916. Serial No. 96,542.

To all whom it may concern:

Be it known that I, Amman GYsI, pro

. fessor, a citizen of the Republic of Switzerland, residin at Obere Z'alune 10, Zurich, Switzerland, ave invented new and useful Improvements in or Relating to Dental Articulators; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference eing had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

In my earlier United States Patent 1041270 I have disclosed an articulator for artificial teeth, in which the upper part rests with its rear end on two guide-sockets arranged behind the points that correspond to the natural jaw hinges. As hereinafter shown and described, it is necessary, in usin this prior articulator for reproducing the ateral masticating or grinding movement, to exert upon it, by hand, a lateral pressure in order to obtain the correct inward movement corresponding to the forward movement- According to the present invention, the

guide-sockets are arranged in the commongeometrical centers of the opening angle and the angle of lateral grinding movement of the'set of teeth. The result of this is, that the hinge points perform in a positive manner, and without any special pressure, a natural inward movement in addition to their forward movement. Thus, the present articulator is a simpler construction and is easier to handle.

A construction according to this invention is illustrated, by way of example, in the accompanying drawing, in which Figure l is a perspective view of the articulator, the lower jaw being shown in dotand-dash lines.

Fig. 2 is a vertical section, the dot-anddash lines representing a set of teeth mounted in the articulator and the upper set of these teeth being shown in its foremost position.

Fig. 3 is a corresponding section, the dot and-dash lines illustrating thelower jaw.

Fig. dis a plan and Figs. 5 and 6 show the difference in the -manner of operation during the lateral masticating or grinding movement between my older articulator and the articulator forming the object of this invention.

In Figs. 1 to 4, 1 denotes the upper and 2 the lower part of the articulator. 3 (Fig. 2) denotes the gypsum block to which is attached the wax plate 4: carrying the set of teeth intended for the upper jaw. 5 is the gypsum block to which is attached the wax plate 6 carrying the set of teeth intended for the lower jaw.

The part 1 is supported at the front by means of a pin 7 adjustable in a vertical direction and having a vertically adjustable cross pin *8 adapted to fix the front cutting tooth edge I. At its rear end, the upper part 1 is provided with diverging arms 9, which end in downward bent points 10 and 11- constituting the rear supports of the upper part 1. The pin 7 rests on an inclined plate 12 that forms an angle of 40 with the horizontal grinding plane AB. The points 10 and 11 rest in guide sockets 13 and 14, the guiding surfaces of which have an average inclination of 33 to the grinding plane A-B.

The upper part 1 is further provided with an interchangeable, horizontal pin 15, mounted in such a way, that, as shown in Fig. 1, points of this pin 15 fall into theline connecting the natural jaw hinges 16 of a lower jaw supposedto be placed in the articulator.

The points II and III on the pin 15 form with the front cutting tooth edge I an equilateral triangle (Fig. 1).

In the older type of articulator before mentioned, the point of support a had the same position as in the present articulator, while the points of support -b and c were so situated as shown by the point I insane? -;-b in1 ig. 3, so'that the guide-sockets were also placed behind the polnts corresponding to thenatural jaw hinges 16.

According to the'present invention, the

points b. and '-carearranged still farther backward andoutward, so that they coincide with the common geometrical centers of the opening angle and the angle of lateral grinding movement of the set of teeth. I I Strictlyspeaking, would be the cor rect geometrical opening center, to which correspond the paths of the opening movement. -aZ- of the molars, the paths -,d

of the incisorsand the path d2 of the front supporting point, a.. In Fig. 3 t will be seen, however, thatin shifting this center to -b or respectively, the resulting paths of the opening movement -f, --f f are practically identical with the paths --d=, l d so that the new artic'ulatorwill work with the required exactness in the case of normal sets of artificial teeth. c

On the other hand, quite anew eflect' is obtained with regard to the lateral masticating or grinding, movement. In the older type of articulator, where the centers of rotation b 'c were situated midway between the hinges 16 and the planeof the teeth A-B, and about one centimeter behind. 16 (Figshl and 3),it will be seen in Fig. 5, that upon a rotation about 0 the joint II moves toward b while upon a rotation about b joint III moves toward -c In order, however, to correspond to the natural grinding movement, the joint II should move toward t* and the I joint III toward 0 qIoattain this lattimeters behind the hinges 16, 2'. e. the points II and III, and are moreover farther apart than these latter points. Upon a rotation of the jaw about b or -c-,. the joints II or III are not onlymoved forwardin a positive manner, but also inward and directly toward the points --fb* and -c, respectively, so that no hand pressure has to r be exerted upon the articulator.

In the case of such lateral grinding movement, the pin 7 (Figs. 2 and 4) slides upward, in one of the two lateral positions 7 (Figs. 2 and 4:), along one of the paths described. I

3. An articulator for artificial sets of shown in Fig. 1 indotted lines and having an inclination of about 40, while the point b or c, respectively, slides upward along the guiding surface of one of the guidin -sockets having an average angle of inclination of 33. The same movements occur in the'case of the forward grinding move ment. The effect thus obtained is,as shown in Fig. ,2, that the incisors move ata different angle thanthe molars, which movement corresponds to the natural movement of the setof teeth. I i

Having now particularly described and ascertained the nature of my said invention,

and in what manner the same is to be performed, I'declare that what I claim is:

1. An articulator for j artificial sets of teeth, comprising a lower articulator part provided with two guide-sockets integral with the uprights of the lower frame and arranged behind the. points corresponding to the natural jaw hinges and lying in common geometrical centers of the opening angle and the angle of lateral grindingmovement of the set of teeth and an upper articulator part, the downwardbent rear end of which rests on said guide-sockets," substantiallyas described. y I y 2. An articulator for artificial sets of teeth, comprising a lowerarticulator part provided with two guide-sockets integral with the uprights of'the lower frame and arranged behind the points corresponding to the natural jawhinges and lyingin common geometrical centers ofthe opening angle and theangle of lateral grinding movement of the set of teeth, said sockets being provided with a guiding surface having an angle of inclination of 33 to the grinding plane, a front guiding surface on said lower articulator part having an angle of inclination of 40 to the grinding plane and an upper articulator part provided with rear supports restin with their bentends on said incllnedsur aces of the guide-sockets and a front support resting on theinclined front guiding surface of the lower articulatorpart,

the rear supports of this upper articulator part beingmoved during the lateral grinding movement upward and rearward along the inclined surfaces of the sockets, while the front support is moved in the same wa along its guiding surface, substantially as teeth, comprising a lower artioulator part having two ide-sockets integral with the uprights of t e lower frame and arranged be hind the points corresponding tothe natural jaw hinges and lying in common geometrical centers of the opening angle and the an-,

gle of lateral grinding movement of the setv 1,228,667 I a m oi teeth and an upper articulator part, the In testimony that I claim the foregoing as downward bent rear end of which rests on my invention, I have signed my name in 10 said guide sockets, and a horizontal pin inpresence of two subsgribing witnesses. terchangeably mounted at the upper articu- ALFRED GYSI I 5 lato'r part in such a way that points of the pin fall into the line connecti n the natural Witnesses: jaw hinges of a lower jaw p aced in the CARL Gunman, articulator, substantially as described. ARNOLD LEHNER. 

